78 EIGHTH REPORT — 1838. 



On tlie Red Sandstone of the Tweed and Carlisle. By Nicholas 

 Wood, F.G.S. 



The author, referring to his memoir in the Transactions of the Natural 

 History Society of Newcastle, described the inclined beds of red sand- 

 stone which rise out from under the mountain-limestone seric"s on the 

 sea coast, about a mile south of the Tweed. He stated his belief that 

 these beds flatten towards the west, so as to form the great deposit of red 

 sandstone of the Tweed, and supported this opinion by a section from 

 Berwick to tiie porphyi-itic hills of the Cheviot range near Barmouth. 

 In the line of tiiis section the relation of the red sandstone in ques- 

 tion to subjacent coal-beds and overlying shales of the limestone series 

 is clearly seen, and the flattening of the strata previously alluded to is 

 witnessed at many points. The most conclusive evidence on this subject 

 is obtained at the coal-workings on the south side of the Tweed. Near 

 their junction with the porphyritic rocks south of Barmouth, the red 

 sandstones assume inclined, vertical, or even reversed positions. — From 

 all his inquiries Mr. Wood infers that the beds of red sandstone of the 

 Tweed are referable to the series lying immediately below the moun- 

 tain limestone and reposing upon the old red sandstone. 



The second part of the paper was illustrated by a section on the line 

 of the nortli side of the ' Great Dyke ' from the sea-side at Cullercoats 

 near Newcastle to Croglin-fell in Cumberland, showing the position of 

 the detached western coal-fields of Stublick, Hartley Burn, Midge- 

 holme, &c. From Midgeholme the strata rise rapidly west, so that the 

 limestone rocks come to the day, and one included coal seam is worked 

 inTindal-fell, and at Talkin, and crops out on the escarpment of Crog- 

 lin-fell. Below this coal-bed appears a series of limestones, the ' whin 

 sill,' a second layer of basalt, limestones and sandstones, and, in some 

 of the deep ravines, beds of red sandstone lying underneath the lime- 

 stones. 



The author compares with this mighty escarpment of the carboniferous 

 limestone, thus based on red sandstone, the analogous and probably con- 

 temporaneous section of Tweeddale, and further declares his conviction 

 that the vale of tlie Eden as well as the vale of tlie Tweed rests on red 

 sandstones, which rise from beneath the escarpments of limestone. In 

 support of this opinion he states that the red sandstones of Cumber- 

 land and the Tweed are very similar, and that they occupy precisely 

 the same relative geographical position to the series of neighbouring 

 mountain limestones. 



The coal of Sanquhar and Cannoby was noticed in connexion with 

 this subject ; and regarding the latter, the author affirms it to be worked 

 under limestones and red sandstones, and that extensive beds of red 

 sandstone overlie this coal formation, and stretch from thence to the 

 Solway Firth, while the coal strata are cut oflT on the north against the 

 transition rocks. Mr. Wood entertains little doubt that the coal series 

 of Dumfries-shire is to be placed on the same parallel as that of Ber- 

 wickshire. 



The opinions thus advanced and supported were compared with the 



